Subseasonal precipitation forecasts of opportunity over central southwest Asia

Abstract. Subseasonal forecasts of opportunity (SFOs) for precipitation over southwest Asia during January–March at lead times 3–6 weeks are identified using elevated expected forecast skill from a linear inverse model (LIM), an empirical dynamical that uses statistical relationships to infer the predictable dynamics system. The this LIM, which is based on atmospheric circulation, tropical outgoing longwave radiation, and sea surface temperatures, captures predictability associated with many relevant signals as opposed just one. Two modes variability, El Niño–Southern Oscillation (ENSO) Madden–Julian (MJO), themselves because their slow variations, related SFOs. Strong Niño events, observed in 1983, 1998, 2016, significantly increase likelihood by up 3-fold SFO 3–4 5–6 advance. La Niña 1989, 1999, 2000, also those same times. High-amplitude MJO events phases 2–4 6–8 greater than one standardized departure Predictable circulation patterns preceding anomalously wet periods indicate role enhanced convection South Pacific convergence zone (SPCZ) region, while suppressed dry periods. Anomalous heating region found distinguish both conditions, although response differs between each ENSO phase.